WO2006040864A1

WO2006040864A1 - Abrasive pad

Info

Publication number: WO2006040864A1
Application number: PCT/JP2005/012903
Authority: WO
Inventors: Toshihiro Izumi; Jun Tamura; Takuya Nagamine; Takashi Arahata
Original assignee: Nihon Microcoating Co., Ltd.
Priority date: 2004-10-14
Filing date: 2005-07-13
Publication date: 2006-04-20
Also published as: US20060229000A1; JP2006110665A; EP1800800A4; TW200611783A; EP1800800A1; KR100804344B1; KR20060080201A; CN1905991A

Abstract

An abrasive pad with which the surface of a wafer can be evenly flattened in a short time. It is a rigid abrasive pad having a high recovery from compression and a low compressibility. The abrasive pad (10) is constituted of a sheet-form pad main body (11) made of a nonfoamed synthetic resin. The pad main body has a shore D hardness of 66.0-78.5, desirably 70.0-78.5, preferably 70.0-78.0, more desirably 72.0-76.0. The compressibility of the pad main body is 4% or lower, preferably 2% or lower. The recovery from compression of the pad main body is 50% or higher, preferably 70% or higher.

Description

Specification

Polishing pad

Technical field

TECHNICAL FIELD [0001] The present invention relates to a polishing pad used for polishing an object requiring high flatness on the surface, such as a semiconductor wafer and a magnetic hard disk substrate, and more particularly to a wafer in a semiconductor device manufacturing process. The present invention relates to a polishing pad suitable for use in planarization.

Background art

[0002] In a semiconductor device manufacturing process, metal wiring layers for interconnecting elements such as transistors, capacitors, resistors, etc. are multilayered. This multilayer wiring is generally performed by using an optical lithography technique or a damascene method. In optical lithography technology, a wiring pattern is exposed and metal wiring is laminated, but when an interlayer insulating film is deposited on the metal wiring layer or the like, a step is generated on the surface of the device. If the unevenness of the pattern becomes larger than the depth of focus of exposure, the accuracy of the width and shape of the pattern decreases, resulting in a problem that the yield of semiconductor devices decreases. (In other words, by reducing the unevenness on the surface of the device formed by the above steps, it is possible to secure an exposure margin for optical lithography, and to perform fine patterning and etching of the wiring layer with high accuracy and ease. In addition, in the damascene method, wiring metal (Cu) is deposited after forming the wiring trench on the insulating film, and polishing is performed to leave the wiring metal only in the trench, thereby providing multilayer wiring. However, there is a problem that the center of the metal wiring becomes thinner (dishing) due to polishing. For this reason, planarization of the device surface (planarization) is an important process in the semiconductor device manufacturing process.

[0003] This planarization is performed using a chemical mechanical polishing (CMP) (hereinafter referred to as CMP) technique. This CMP chemically dissolves the surface of the device with the machining fluid and mechanically scrapes it with the gunshot, that is, combines the chemical removal action with the machining fluid and the mechanical removal action with the gunball. Polishing technology and processing This is a widely used polishing technique because it hardly causes a deteriorated layer (a part of the surface different from the inside caused by processing).

[0004] This planarization by CMP rotates a surface plate (or platen) on which a polishing pad is mounted, and fine polishing particles selected from particles such as silica, alumina, ceria, and zirconia on the surface of the polishing pad. A slurry in which grains are dispersed in an alkaline or acidic working fluid is supplied, and a wafer surface (that is, a device surface) attached to a polishing head (or carrier) is pressed onto the slurry.

[0005] Generally, as a polishing pad, a foam pad (eg, Rohm 'and' Hearth. Electronic. Materials') that also has foam strength such as polyurethane having a large number of pores formed by bubbles when foamed inside. The product number IC1000) available from C.M.P.Holdings'Incorporated is used.

[0006] However, the foam pad is easy to compress and easily deforms (high compression ratio). Therefore, the foam pad is elastically deformed and enters the recess on the surface of the device, and the recess is scraped into the recess in the process of flattening. Thus, a residual step is generated. Also, in the foam pad, the density of pores inside the pad is uneven, so even if the wafer surface is pressed against the pad surface with a constant polishing pressure, the repulsive force of the pad against this polishing pressure becomes non-uniform, The pad surface cannot be applied uniformly over the wafer surface, and the wafer surface cannot be uniformly polished. For this reason, the amount of polishing at each point on the wafer surface varies.

For this reason, a hard polishing pad, that is, a pad obtained by curing a synthetic resin such as polyurethane without foaming (hereinafter referred to as a non-foamed pad) has been proposed (patented). Reference 1). This non-foam pad is difficult to compress (low compression rate) and recovers slowly from deformation due to compression (low compression recovery rate) (ie, low elastic repulsion). Intrusion and shaving in the recesses were reduced, which reduced the occurrence of residual steps. Further, in this non-foamed pad, the polishing rate is remarkably lowered as compared with the foam pad. Therefore, a groove pattern is formed on the pad surface to improve the polishing rate.

Patent Document 1: Special Table 2004-507077

Disclosure of the invention Problems to be solved by the invention

However, merely forming a groove pattern on the pad surface as described above can only achieve a polishing rate comparable to that of the above foam node, and cannot achieve a higher polishing rate. .

Further, in such a non-foamed pad, since pores are formed inside, the repulsive force of the pad against the polishing pressure is uniform over the wafer surface, and the pad surface is uniform over the wafer surface. However, since the compression recovery rate is low, the elastic repulsive force of the pad varies at each point in the wafer surface where it is difficult to follow the unevenness of the device surface. The surface of the wafer cannot be uniformly applied over the wafer surface, and the amount of polishing at each point on the wafer surface varies, and the surface of the wafer cannot be uniformly polished.

[0010] Therefore, an object of the present invention is to provide a polishing pad that can uniformly flatten the surface of a wafer (that is, the surface of a device) in a short time.

Means for solving the problem

[0011] As described above, when the compression recovery rate of a polishing pad having no foam is reduced,

However, it is considered that the amount of polishing at each point in the surface of the object to be polished (wafer) varies, and on the other hand, when the compression recovery rate is increased, the elastic repulsive force increases and a residual step is generated. However, as a result of diligent research, the inventors of the present invention have optimized the hardness (in the present invention, the hardness is indicated by using the Shore D hardness) in a non-foamed pad having a high compression recovery rate and a low compression rate. As a result, it was found that the residual level difference can be reduced and the surface can be uniformly flattened at a high polishing rate.

The polishing pad of the present invention that achieves the above object is composed of a sheet-like pad body made of synthetic resin and having no foam.

[0013] Shore D hardness of the knot body ί, range from 66.0 to 78.5, preferably from ί to 70.0 to 78.5, more preferably from ί to 70.0 to 78.0. Furthermore, this is preferably in the range of 72.0 to 76.0.

[0014] The compression ratio of the pad body is in the range of 4% or less, preferably in the range of 2% or less.

[0015] The compression recovery rate of the pad body is in the range of 50% or more, preferably in the range of 70% or more. [0016] In order to reduce the hydroplane phenomenon on the surface of the knot body, the groove portion formed on the surface of the pad body may be subjected to groove processing (when the surface of the pad body is viewed in plan view). The ratio of the groove area) to the entire surface of the pad body is in the range of 10% to 50%, with the entire surface of the pad body being 100%.

[0017] Further, in the present invention, in order to improve the followability of the polishing pad to the surface to be polished, the backing sheet may be fixed to the back surface of the pad body as a backing sheet. An elastic sheet having a compression ratio lower than the D hardness and higher than the compression ratio of the pad body is used.

[0018] Further, the pad main body may transmit light 0.5mn! To 2. The thickness of the pad body in the range of Omm, the light transmittance of the pad body of light in the wavelength range of 350 nm to 900 nm is in the range of 10% or more, preferably 0 In the thickness of the pad body in the range of 5 mm to 2. Omm, the light transmittance of the light in the wavelength range of 450 nm to 900 nm is in the range of 30% or more.

The invention's effect

Since the present invention is configured as described above, the surface of the wafer (ie, the surface of the device) has a high polishing rate (for a short time), and the amount of polishing at each point on the wafer surface does not vary. There is an effect that the residual level difference can be reduced (flattened) uniformly.

BEST MODE FOR CARRYING OUT THE INVENTION

As shown in FIG. 1A, the polishing pad 10 of the present invention is composed of a sheet-like pad body 11.

[0021] The pad main body 11 is a non-foamed synthetic resin selected from known thermoplastic or thermosetting resins such as polyester, polyurethane, polypropylene, nylon, acrylic, and epoxy. Physical strength.

[0022] The node body 11 is prepared by adding a resin solution prepared by adding a curing agent to a synthetic resin into a mold and curing the resin solution in the mold to form a non-foamed block. Can be sliced to the desired thickness. In addition, manufacture using known sheet forming techniques such as extrusion and injection molding. [0023] The thickness of the pad main body 11 is not particularly limited, but is preferably in the range of 0.5 mm to 2. Omm.

[0024] The Shore D hardness (measured with a Shore D hardness meter based on JIS L-1096) of the Nod body 11 is in the range of 66.0 to 78.5 when measured at a temperature of 23 ± 3 ° C. It is preferably in the range of 70.0 to 78.5, more preferably in the range of 70.0 to 78.0, and still more preferably in the range of 72.0 to 76.0. Since the polishing pressure when using the polishing pad 10 of the present invention (described later with reference to FIGS. 2A and 2B) is practically less than 15 psi, it is preferably within 15 psi, more preferably lpsi. It is in the range of ~ 10psi. In this polishing pressure range (15 psi or less), if the Shore D hardness of the pad main body 11 is less than 66.0, the pad main body will be deformed so that each point on the surface of the object (wafer) will be deformed. If the pad D has a Shore D hardness of more than 78.5, the pad body will not be deformed, and the followability of the nod body 11 to the workpiece will be reduced. This can cause scratches on the surface of the object.

[0025] The compressibility is measured at a temperature of 23 ± 3 ° C. 1. The pad body thickness at a load of 4 psi is 0 (zero), and the thickness of the pad body at a load of 16 psi is The amount of change is expressed in%. In the present invention, the compression ratio of the knot body 11 is in the range of 4% or less, preferably in the range of 2% or less. If the compression ratio exceeds 4%, the inside of the recess on the wafer surface (device surface) will be cut too much, causing residual steps.

[0026] The compression recovery rate is determined by measuring the displacement of the pad body under a load of 16 psi when measured at a temperature of 23 ± 3 ° C. Next, after reducing the load to 1.6 psi, measure the displacement recovered in 30 seconds and divide this recovered displacement by the displacement at the 16 psi load described above (ie, compressed The ratio of the recovered displacement amount to the displacement amount (%)). In the present invention, the compression recovery rate of the pad body 11 is in the range of 50% or more, preferably in the range of 70% or more. If the compression recovery rate is less than 50%, the elastic resilience of the pad varies at each point in the wafer surface where it is difficult to follow the unevenness of the device surface, and the nod surface is evenly distributed over the wafer surface. The surface of the wafer cannot be uniformly polished due to variations in the polishing amount at each point on the wafer surface.

[0027] The nod body 11 prevents the wafer from adsorbing on its surface and reduces the hydroplane phenomenon. In order to reduce the groove, the groove area formed on the surface of the pad main body 11 (the groove area when the surface of the pad main body is viewed in plan view) is spread over the entire surface of the pad main body. The occupied ratio is in the range of 10% to 50% with the entire surface of the pad body as 100%. The shape of the groove is formed by a concentric circle shape, a lattice shape, etc., a curved line, a straight line, or a geometric pattern combining these.

In addition, as shown in FIG. 1B, in order to improve the followability to the surface to be polished of the polishing pad 10 of the present invention, a backing sheet 13 is fixed to the back surface of the pad body 11 with an adhesive 12. Also good. As the backing sheet 13, an elastic sheet having a hardness lower than the Shore D hardness of the pad body 11 and a compression rate higher than the compression rate of the pad body 11 is used. As the elastic sheet, a sheet having foam strength such as polyurethane can be used.

<Embodiment> When a semiconductor device is manufactured, if an interlayer insulating film is deposited on a metal wiring or the like formed on the wafer, it is generated on the surface of the wafer. In accordance with the present invention, this step is removed and the wafer surface (device surface) is planarized.

[0030] A CMP (chemical mechanical polishing) apparatus 20 as shown in FIGS. 2A and 2B is used to planarize the surface of the wafer.

As shown in FIG. 2A, in polishing the surface of the wafer 26, first, the polishing pad 10 is attached to the surface of the surface plate (or platen) 21 via an adhesive tape, and the surface plate 21 is rotated. Slurry is supplied to the surface of the polishing pad 10 through the nozzle 23, and the surface of the wafer 26 attached to the polishing head (or carrier) 22 is pressed against the surface of the polishing pad and rotated.

[0032] The example shown in FIG. 2B is a polishing technique for detecting the end point of polishing by irradiating light on the surface of the wafer being polished (this technique is called end point detection polishing). Mount the surface plate (or platen) 2Γ on the surface of the surface using adhesive tape and rotate the surface plate 2Γ. The slurry is supplied to the surface of the polishing pad 10 through the nozzle 23, and the surface of the wafer 26 attached to the polishing head (or carrier) 22 is pressed against the surface of the polishing pad and rotated. During polishing, the surface of the wafer 26 is irradiated with light 25 from the light source 24 through the through hole of the surface plate 2 /, and the reflected light 25 is monitored (reference numeral 24) to detect the end point of polishing and finish polishing.

[0033] When the polishing pad 10 of the present invention is used for this end point detection polishing, A transparent one is used. The light transmittance of the pad body 11 is in the range of 10% or more for light in the wavelength range of 350 nm to 900 nm when the thickness of the pad body 11 is in the range of 0.5 mm to 2. Omm. Yes, preferably, when the thickness of the pad body is in the range of 0.5 mm to 2.0 Omm, in the light in the wavelength region of 450 nm to 900 nm, it is in the range of 30% or more.

In the CMP apparatus 20 shown in FIGS. 2A and 2B, a retainer ring (not shown) is attached to the polishing head 22 outside the peripheral portion of the wafer. This retainer ring is pressed by the pressure applied to the ring part and easily occurs at the periphery of the wafer! / Prevents over-polishing, and the wafer is detached from the polishing head due to lateral stress generated during polishing. To prevent this. Further, in order to reduce the influence of the groove processing applied to the polishing pad 10, the polishing head 22 is reciprocated (oscillated) in the radial direction of the surface plates 21, 2Γ during polishing.

[0035] Although not shown, the CMP apparatus 20 shown in FIGS. 2A and 2B eliminates clogging of the surface of the polishing pad 10 due to polishing debris generated during polishing, or wear of the polishing pad 10 causes wear. A dressing tool such as a diamond dresser can be provided to remove the deformation of the surface of the polishing pad 10. Dressing is performed by pressing a dressing tool while supplying water to the surface of the polishing pad 10 attached to the surface of the rotating surface plates 21 and 2Γ.

[0036] A slurry is used in which a barrel is dispersed in water or a water-based aqueous solution, and a reaction solution (sodium hydroxide, ammonia, etc.) that chemically reacts with substances on the wafer surface is added. .

[0037] The pressure (polishing pressure) that presses the wafer 26 against the surface of the polishing pad 10 (ie, the surface of the pad body 11) is in the range between lpsi and 10 psi.

[0038] <Example 1> A TDI (tolylene diisocyanate) urethane prepolymer (100 parts) having an average molecular weight of about 750 was used as a curing agent, and 3, 3'-dichloro 4, 4 'diamino monodifa- Lumetane (26.5 parts) was added to prepare a tanning solution. This resin solution is put into a mold and cured in the mold to form a non-foamed block, which is sliced to a thickness of 1.5 mm and has a Shore D hardness of 78.0 (measured) A pad body with a temperature of 23.0 ° C is manufactured, and a groove is machined on the surface of this pad body using a lathe (groove shape: spiral, groove size: land width 0.6 mm Z groove A polishing pad of Example 1 was obtained by applying a width of 0.3 mm and a groove occupation ratio of 33.3%.

<Example 2> To a TDI-based urethane prepolymer (100 parts) having an average molecular weight of about 900, 3,3′-dichloro 4,4 diamino-difatal methane (26.5 parts) was used as a curing agent. The solution was prepared by simmering. This resin solution is put into a mold and cured in the mold to form a foam-free block, which is sliced to a thickness of 1.5 mm, and Shore D hardness 75.0 ( Manufacture a pad body with a measurement temperature of 23.0 ° C, and use a lathe on the surface of this pad body to form grooves (groove shape: spiral, groove size: land 0.6 mm, Z groove 0.3 mm, groove occupancy 33 3%), and this was used as the polishing pad of Example 2.

<Example 3> To a TDI-based urethane prepolymer (100 parts) having an average molecular weight of about 960, 3, 3′-dichloro 4,4 diamino-difatal methane (26.3 parts) was used as a curing agent. A cocoa solution was prepared by adding calories. This resin solution is put into a mold and cured in the mold to form an unfoamed block, which is sliced to a thickness of 1.5 mm, and a Shore D hardness of 72.0 (measured) Manufacture a pad body with a temperature of 23.0 ° C and use a lathe on the surface of this pad body to form grooves (groove shape: spiral, groove size: land 0.6 mm, Z groove 0.3 mm, groove occupancy 33. 3%), and this was used as the polishing pad of Example 3.

<Example 4> A TDI urethane prepolymer (100 parts) having an average molecular weight of about 1080, and 3, 3′-dichronole 4, 4 diamine monodifatal methane (26.0 parts) as a hardener. ) Was added to prepare a rosin solution. This resin solution is put into a mold and cured in the mold to form a non-foamed block, which is sliced to a thickness of 1.5 mm and has a Shore D hardness of 66.0 (measurement) A node body with a temperature of 23.0 ° C was manufactured, and a groove was formed on the surface of this pad body using a lathe (groove shape: spiral, groove size: land 0.6 mm, Z groove 0.3 mm, groove occupancy 33. 3%), and this was used as the polishing pad of Example 4.

<Comparative Example 1> HDI (hexamethylene diisocyanate) urethane prepolymer (100 0 咅, 3, 3'-dichloronone 4,4 'diamine nofino methane (47 3) was added to prepare a tanning solution, which was poured into a mold and hardened in the mold to form a non-foamed block. To produce a knot body with a Shore D hardness of 80.0 (measuring temperature 23.0 ° C), and using a lathe on the surface of the knot body (groove shape: spiral, groove) Size: Land 0.6mm Z groove 0.3mm, groove occupation A polishing pad of Comparative Example 1 was obtained.

<Comparative Example 2> To a TDI urethane prepolymer (100 parts) having an average molecular weight of about 1260, as a hardener, 3, 3'-dichronore 4, 4 diamine monodifatal methane (23.0 parts) ) Was added to prepare a solution. This resin solution is put into a mold and cured in the mold to form a non-foamed block, which is sliced to a thickness of 1.5 mm and has a Shore D hardness of 60.0 (measured) Manufacture a pad body with a temperature of 23.0 ° C and use a lathe on the surface of this pad body to form grooves (groove shape: spiral, groove size: land 0.6 mm, Z groove 0.3 mm, groove occupancy 33. 3%), and this was used as the polishing pad of Comparative Example 3.

[0044] Comparative Example 3> As a polishing pad of Comparative Example 3, a commercially available foam pad (Product No .: IC100 0, Rohm & Haas · Electronic · Materianoles 'Cm · P · Holdings' Incorporated )It was used. The thickness of the polishing pad of Comparative Example 3 was 1.25 mm, and the Shore D hardness was 59.0.

The Shore hardness, compression rate, and compression recovery rate of each of the polishing pads of Examples 1 to 4 and Comparative Examples 1 to 3 are shown in Table 1 below.

[Table 1] Table 1

<Comparative Test 1> Using the polishing pads of Example 3 and Comparative Example 3 respectively, the surface of the wafer was polished, and the steps on the surface of the wafer were compared with each polishing pad. [0047] As the wafer, a known test wafer (SKW7-2) generally used widely in the flatness evaluation test was used. This test wafer is obtained by etching the surface of a silicon substrate with a predetermined mask pattern and depositing a silicon oxide film thereon by CVD. In this comparative test 1, the steps of the patterns D20, D40 and D80 with respect to the polishing amount of the pattern D100 of the test wafer after polishing with each polishing pad were compared. (Here, pattern D100 is a part on the test wafer without unevenness, and pattern D20 is a linear convex part with a width of 20 m and a linear concave part with a width of 80 m and a depth of 0.8 m. The pattern D40 has alternating 40 μm wide linear protrusions and 60 μm wide and 0.8 m deep linear recesses alternately. Pattern D80 is an area on the test wafer that is formed, and linear protrusions with a width of 80 μm and linear depressions with a width of 20 μm and a depth of 0.8 μm are alternately formed. (A commercially available level difference measuring device (product number: P-1, Tencor Corporation) was used to measure the unevenness on the test wafer.)

[0048] As a polishing apparatus, a commercially available CMP apparatus (product number: MAT-ARW68 1S, EM Corporation) as shown in FIG. 2A was used. The polishing conditions were as shown in Table 2 below. In addition, a slurry obtained by diluting a commercially available slurry stock (Product No .: Semi Sperse25, Cabobot • Microelectronics • Japan Co., Ltd.) twice with pure water (stock solution: pure water = 1: 1) was used.

[Table 2] Table 2

Polishing conditions

Constant speed 6 0 r p m

Polishing head speed 6 3 r p m

Polishing head load (Polishing pressure) 3 p s i

Retainer ring load 5 p s i

Oscillation speed 1 m mZ min

Oscillation distance 10 m m

Slurry flow rate 2 0 0 cc min [0049] The results of Comparative Test 1 are shown in FIG. As shown in Figure 3, each pattern (D20, D40, D80) on the test wafer is flattened in a shorter time by using the polishing pad of Example 3 than when using Comparative Example 3. It can be seen that a smooth surface was obtained.

<Comparative Test 2> Using the polishing pads of Examples 1, 2, and 4 and Comparative Examples 2 and 3, respectively, the surface of the wafer was polished, and the level difference on the surface of the wafer was measured with each polishing pad. Compared.

[0051] As in the comparative test 1, a known test wafer (SKW7-2) generally used widely in the flatness evaluation test was used as the wafer. In this comparative test 2, the level difference of the pattern D80 with respect to the polishing amount of the pattern D100 of the test wafer after polishing with each polishing pad was compared.

[0052] As the polishing apparatus, a commercially available CMP apparatus (product number: MAT-ARW68 1S, EM Corporation) as shown in FIG. 2A was used. The polishing conditions were as shown in Table 2 above. In addition, a slurry obtained by diluting a commercially available slurry stock (Product No .: Semi Sperse25, Cabobot • Microelectronics • Japan Co., Ltd.) twice with pure water (stock solution: pure water = 1: 1) was used.

[0053] The results of Comparative Test 2 are shown in FIG. As shown in Fig. 4, the pattern D80 on the test wafer is flattened in a shorter time by using the polishing pads of Examples 1, 2, and 4 than when using Comparative Examples 2 and 3. It can be seen that a smooth surface was obtained.

[0054] Comparative Test 3> Using the polishing pads of Examples 1, 2, and 4 and Comparative Examples 1 to 3, respectively, a plasma oxide film without a pattern on the surface was formed (thickness 10000A). The surface of a wafer with a PTEOS film (diameter 200 mm) was polished, and the polishing rate and in-plane uniformity were compared for each polishing pad. Here, in-plane uniformity (abbreviation of WIWNU: within wafer non-uniformity) is a parameter indicating the processing uniformity within the wafer surface, and the standard deviation of the polishing amount at each point in the surface. The average X 100 (%) indicates that the smaller the wiwnu value, the less variation in the polishing amount at each point in the plane. In addition, the film thickness measurement performed for the measurement of the polishing amount was performed using a commercially available optical interference type film thickness measuring device (product number: Nan _OS pe _C 9200, Nanometrics Co., Ltd.).

[0055] As the polishing apparatus, a commercially available CMP apparatus (product number: MAT-ARW68 1S, EM Corporation) as shown in FIG. 2A was used. The polishing conditions are as shown in Table 3 below. I got it. In addition, a slurry obtained by diluting a commercially available slurry stock (Product No .: Semi Sperse25, Cabobot Microelectronics Japan Ltd.) twice with pure water (stock solution: pure water = 1: 1) was used.

[Table 3] Table 3

Polishing conditions

[0056] The results of Comparative Test 3 are shown in Table 4 below. Each measured value is shown in FIG. 4A (polishing rate) and FIG. 4B (in-plane uniformity). FIG. 5 is a composite diagram of FIGS. 4A and 4B.

[Table 4] Table 4

Results of comparative test 3

(Each numerical value is a measured value based on measurements from the center to the essence of 5 mm)

The polishing rate of Comparative Example 3 is 2000 A / min, and the in-plane uniformity is 7.296.

A practically required polishing rate is 1700 AZ or more, and in-plane uniformity is 8.0% or less.

[0058] As shown in FIGS. 4A and 4B (and FIG. 5), the polishing rate and in-plane uniformity required for practical use are uniform. Properties are achieved in the range between Shore D hardness 66.0-78.5.

In addition, as shown in FIG. 4A (and FIG. 5), the Shore D hardness is 70.0- because the polishing rate is higher than Comparative Example 3 in the range of Shore D hardness of 70.0 or more. It can be seen that the practically required polishing rate and in-plane uniformity are achieved in the range between 78.5 and at least higher than the polishing rate of Comparative Example 3.

[0060] Further, as shown in FIG. 4B (and FIG. 5), in the range of Shore D hardness between about 64.0 and 78.0, the in-plane uniformity is lower than that of Comparative Example 3, so that the Shore In the range of D hardness between 70.0 and 78.0, the above-mentioned practically required polishing rate and in-plane uniformity are achieved, and the in-plane uniformity is higher than the polishing rate of Comparative Example 3. Is low. In addition, the lowest in-plane uniformity is achieved when the Shore D hardness is between 72.0 and 76.0.

Brief Description of Drawings

[0061] FIG. 1A and FIG. 1B are cross-sectional views of a polishing pad according to the present invention.

FIG. 2A and FIG. 2B show a polishing apparatus.

FIG. 3A is a plot of the step with respect to the polishing amount of Example 3 and Comparative Example 3, and FIG. 3B is a plot of the step with respect to the polishing amount of Examples 2, 4 and Comparative Examples 2 and 3.

[FIG. 4] FIG. 4A shows the polishing rate plots for the Shore D hardness of Examples 1 to 4 and Comparative Examples 1 and 2 and the polishing rate of Comparative Example 3. Examples 1 to 4 and Comparative Examples 1 and 2 This is a plot of in-plane uniformity versus Shore D hardness and in-plane uniformity of Comparative Example 3.

FIG. 5 is a composite diagram of FIGS. 4A and 4B.

Explanation of symbols

[0062] lO-• Polishing pad

l l-• knot body

12 · “Adhesive

13 · · · Back sheet

20CMP equipment

21, 2Γ… Surface plate

22 • Polishing head …nozzle

... Light source, monitor ... irradiated light, reflected light ... wafer

Claims

The scope of the claims

[1] a polishing pad,

A sheet-like pad body that is made of synthetic resin and has no foam.

Consisting of

The Shore D hardness of the pad body is in the range of 66.0-78.5,

The compression ratio of the pad body is in the range of 4% or less,

The compression recovery rate of the pad body is in the range of 50% or more,

However polishing pad.

[2] The polishing pad of claim 1,

The compression ratio is in the range of 2% or less,

However polishing pad.

[3] The polishing pad of claim 1,

The compression recovery rate is in the range of 70% or more,

However polishing pad.

[4] The polishing pad of claim 1,

The Shore D hardness is in the range of 70.0 to 78.5,

However polishing pad.

[5] The polishing pad of claim 1,

The Shore D hardness is in the range of 70.0 to 78.0,

However polishing pad.

6. The polishing pad according to claim 1, wherein the Shore D hardness is in the range of 72.0-76.0.

[7] The polishing pad of claim 1,

In the thickness of the pad body in the range of 0.5 mm to 2. Omm, the light transmittance of the pad body of light in the wavelength range of 350 nm to 900 nm is in the range of 10% or more.

However polishing pad.

[8] The polishing pad of claim 1,

In the thickness of the pad body in the range of 0.5 mm to 2. Omm, 450 nm to 900 nm the light transmittance of the pad body of light in the wavelength range of nm is in the range of 30% or more,

However polishing pad.

[9] The polishing pad of claim 1,

The surface of the pad body has a groove,

Proportional force occupied by the groove portion with respect to the entire surface of the pad body is in the range of 10% to 50%, where the entire surface of the pad body is 100%.

However polishing pad.

[10] The polishing pad of claim 1,

A backing sheet fixed to the back of the pad body;

A polishing pad that further comprises force.

[11] The polishing pad of claim 10,

As the backing sheet, an elastic sheet having a hardness lower than the Shore D hardness of the pad main body and a compression rate higher than the compression rate of the pad main body is used.

However polishing pad.